High-voltage apparatus such as a circuit breaker or the like equipped with means for preventing impairment of the electric field within the apparatus enclosure

ABSTRACT

A high-voltage apparatus such as a compressed-gas circuit breaker or the like has an enclosure wherein an electric field is present when the breaker is in service. A reinforced housing arrangement accommodates the drive mechanism for actuating the contacts of the breaker and is arranged within the enclosure. The housing arrangement includes a housing member disposed in surrounding relation to the drive mechanism and a plurality of reinforcement ribs are provided on at least the outer surface of the housing member. At least two shell-like members made of electrically conductive material conjointly form a hollow cylinder and are arranged in surrounding relation to the outer surface of the housing member whereby impairment of the electric field within the enclosure is precluded. The shell-like members are secured to the housing member in a self-holding manner.

United States Patent Noack HIGH-VOLTAGE APPARATUS SUCH AS A CIRCUITBREAKER OR THE LIKE EQUIPPED WITH MEANS FOR PREVENTING IMPAIRMENT OF THEELECTRIC FIELD WITHIN THE APPARATUS ENCLOSURE Dieter Noack, Berlin,Germany Siemens Aktiengesellschaft, Munich, German y Filed: May 29, 1973Appl. No.: 364,274

Inventor:

Assignee:

Foreign Application Priority Data May 31, 1972 Germany 2227330 US. Cl.200/148 R; 200/14 D 1m. 01. H0 111 33/82 Field of Search 200/148 1), 148R References Cited UNITED STATES PATENTS 11/1948 Amer 200/148 DFriedrich .1 200/148 D 3.728504 4/1973 Beier 200/148 D PrimaryExaminer-Robert S. Macon Attorney, Agent. or Firml(enyon & Kenyon ReillyCarr & Chapin [5 7 ABSTRACT A high-voltage apparatus such as acompressed-gas circuit breaker or the like has an enclosure wherein anelectric field is present when the breaker is in service. A reinforcedhousing arrangement accommodates the drive mechanism for actuating thecontacts of the breaker and is arranged within the enclosure. Thehousing arrangement includes a housing member dis-' posed in surroundingrelation to the drive mechanism and a plurality of reinforcement ribsare provided on at least the outer surface of the housing member. Atleast two shell-like members made of electrically conductive materialconjointly form a hollow cylinder and are arranged in surroundingrelation to the outer surface of the housing member whereby impairmentof the electric field within the enclosure is precluded. The shell-likemembers are secured to the housing member in a self-holding manner.

5 Claims, 3 Drawing Figures US. Patent Nov. 11,1975 Sheet1of2 3,919,511

U.S. Patent Nov.1l, 1975 Sheet20f2 3,919,511

ao rqao HIGH-VOLTAGE APPARATUS SUCH AS A CIRCUIT BREAKER OR THE LIKEEQUIPPED WITH MEANS FOR PREVENTING IMPAIRMENT OF THE ELECTRIC FIELDWITHIN THE APPARATUS ENCLOSURE I BACKGROUND OF THE INVENTION In ahigh-voltage circuit breakers and particularly in compressed-gas circuitbreakers with several. seriesconnected switchingdevices having switchinglocations arranged on a common axis, a common drivefor the.

switching devices is often provided which opens and closes the contacts'of the switching devices simultaneously. A high-voltage circuit breakerwith two seriesconnected switching devices is described, for instance,in Siemens Zeitschrift, No. 8, August l968, on pages 579 to 583. Theknown circuit breaker, in which sulfur hexafluoride is used as thequenching and insulating. medium, has a drive member which is movablyguided in a direction perpendicular to the axis of the switchingcontacts and is coupled with the drive-rods for the switching contactsvia direction changing linkages, for

instance, by means of angle levers.

If the drive for the switching contacts is also configured so that itinitiates the flow of quenching medium for the switching devices, whichis the case particularly with blast piston systems,it is necessary toconfigure the mechanism housing for the contact drive so that it canresist torsion; this is necessary because of the 1 forces and torquesthat are required and must be transmitted. For this purpose, themechanism housing is provided with stiffening ribs on at least theoutside of the cylinder surface. When the apparatus is in service, themechanism housing is at the high-voltage potential.

Such a configuration of the mechanism housing can lead to distortion ofthe electric field between the outer wall of the housing, particularlythe stiffening ribs, and the grounded breaker enclosure of thecompressed-gas circuit breaker.

SUMMARY OF THE INVENTION Accordingly, it is an object of the inventionto provide a housing arrangement for a high-voltage apparatus such as acircuit breaker or the like whereinimpairment of the electric fieldwithin the apparatus.enclosure is precluded. ltis another object of theinvention to provide a housing-arrangement which achieves the desireableeffect of nonimpairment of the electric field while at the same timeallowing a configuration of the housing thatincludes the structuralreinforcement needed to make the housing resistant to torsional loadingas, for. example, in a housing accommodating the .drive mechanism of acircuit breaker. 1 r

The invention relates to a high-voltage apparatus, and particularly to acompressed-gas'circuit breaker with a mechanism housing foraccommodating the 9 drive of the contacts. The housing is arrangedwithin the breaker enclosure and is at high-voltage potential when thebreaker is in service. The mechanism'housing is provided with stiffeningribs at. least on the outside surface. According to the invention, twohalf-shells of electrically conductive material are provided whichenclose the mechanism housing on the outside surface and together form ahollow'cylinder. The two half disposed in surrounding relation to thedrive mechanism and a plurality of reinforcement ribs are provided on atleast the outer surface of this housing member. At least two shell-likemembers made of electrically conduc'tive material, conjointly form ahollow cylinder and are arranged in surrounding relation to the outersurface of the housing member whereby impairment of the electric fieldwithin the enclosure is precluded. Fastening means are provided forself-holding the shell-like members to the housing member.

According to another feature of the invention, the shell-like memberscan be two in number and can be respective half-shells.

The housing member can have respective end-face portionsextending'radially in covering relation to the reinforcement ribs andthe fastening means can comprise means for self-holding the half-shellsfixedly between the end-face portions.

According to a subsidiary feature of theinvention, the fastening meanscan include slot means formed in each of the end-face portions at theperiphery thereof, and inwardly directed projection means formed on thelongitudinal ends of each of the half-shells for engaging correspondingones of the slot means.

If the compressed-gas circuit breaker is subjected to I I vibrationduring operation which could affectthe electrical contact of thehalf-shells with the drive mechanism housing, it is advantageous toprovide threaded elements which connect the half-shells with themechanism housing.

According to another subsidiary feature, the fastening means comprisesancillary fastening means in the form of a plurality of threaded membersfor joining the half-shells to the end-face portions of the housingmember disposed in surrounding relation to the drive mechanism. I

Although the invention is illustrated and described herein as ahigh-voltage apparatus such as a circuit breaker or the like equippedwith means for preventing impairment of the electric .field within'theapparatus enclosure, it is nevertheless not intended to be limited 'to'the details shown, since various modifications may be made thereinwithin the scope and the range of the claims. The invention, however,together with additional objects and advantages will be best understoodshells snap into parts of the mechanism housing in a self-holdingmanner. In this manner the shielding of the mechanism housing requiredfor the equalization of the from the following description and inconnection with the accompanying drawings.

BRIEF DESCRIPTION OF'TI-IE DRAWINGS FIG. 1 shows, schematically andpartially in section, a circuit breaker 'equipped with a drive housingarrangement for preventing distortion of the electric field according tothe invention. The breaker is of the compressed-gas type and is providedwith a blast-piston arrangement. all:

3 FIG. 2 is an exploded view of the drive housing of the circuit breakerof FIG. 1.

FIG. 3 is a cross-section view taken along the linesllI- -Ill of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION havingacylindrical housing part 2 with three tubular stubs 3, 4 and 5. The endfaces of the cylindrical part 2 are closed by lids 6 and 7. In theinterior 10of the cylindrical part 2, two identical switching devices 11and 12 electrically connected in series are accommodated and aredisposed on a common axis. Associated with each of the switching devicesare two stationary electrodes Band which are'hollow and serve as nozzlesfor the flow of quenching medium.

In the closed position, the electrodes 13, 15 are connected by a hollow,movable contact element 14. Then,

the circuit leads from the electrode 13 which can be stationary contactthrough the contact element 14 to the electrode 15 which directs thecurrent in the manner of a sliding contact to a stationary metal housing16. The housing 16 is the drive mechanism housing and is in the centerbetween the two switching devices 11 and 12. n

The mechanism housing 16 is made of metal and is engaged by ahollowsupport insulator 20 made, for example, of cast resin. The supportinsulator 20 is rigidly connected with the mechanism housing 16 at itshighvoltage end. The grounded end of the insulator 20 which protrudesinto the stub 4 is rigidly connected at a cover 21. The cover 21 is partof the housing of a breaker drive 22, for example, a double-actinghydraulic cylinfder. I

The breaker actuator 22 provides a reciprocating motion of the drivemember 24 in the direction of the axis of the insulator 20. The drivemember 24 consists of insulating material and is guided in the mechanismhousing 16 at the location designated by reference numeral 25. Twooppositely movable direction changing levers 26, 27 are set in motion bymeans of two connecting rods 28, 29 by the movement of drive member 24.The rods 28, 29 are coupled with the movable contacts 14 of theswitching devices 11 and "12 by means control rods 30.

The control rods 30 are further connected with a blast cylinder 31 whichis pulled over a stationary blast piston-32 during the breaker openingoperation, so that the sulfur hexafluoride compressed in this processextinguishes the arc, the compressed gas flowing through the hollowcontacts 13 and 14. i

Referring to FIGS. 2 and 3, the drive 'housing 16 contains a stationarypivot bearing 37 for the levers 26, 27.

The part 16a of housing 16 carries and guides the levers 26, 27.Stiffening ribs 40, the fastening elements for connecting the housingpart 16a with the housing 16 and with the support insulator 20 and alsoprojecting 1 by, two half-shells 41, 42 which form a hollow cylinder andenclose the mechanism housing 160 at the outside surface thereof. Thehalf-shells.have'inwardly directed projecting peripheral flanges 43which snap into parts of the mechanismhousing 16a in a self-holdingmanner. The half-shells 41 and 42 consist of electrically conductivematerial and are connected with metal mechanism housing 16, 16a in anelectrically conducting manner.

In the illustrated embodiment, the mechanism housing includes twoend-face portions 44 which radially cover the stiffening ribs 40. Thehalf-shells 41, 42 are fixed between these two end-face portions 44. Forthis purpose, the endface portions 44 have slots 45 at the peripherythereof in which the inwardly directed projecting peripheral flanges 43of the half-shells 41, 42 I engage. To ensure a permanent, electricallyconducting connection between the mechanism 16, 16a and the half-shells41, 42, an additional connection can be made by means of threadedelements in the form of screws 46 which are advantageously arranged in aThe invention makes it possible to provide a configuration for themechanism housing which is resistant to tension and which does notimpair the electric field in the interior of the grounded breakerhousing.

Although the invention is described in the context of acompressed-gascircuit breaker, it can also be advantageously applied forshielding other components in,

metal-encapsulated, compressed-gas insulated high;- voltage apparatusand installations. Typical of such." components are bus bars, disconnectswitches and the like.

What is claimed is: .v

1. In a high-voltage apparatus such as a compressedgas circuit breakeror the like having an enclosure wherein an electric field is presentwhen the breaker is in service, a reinforced, housing arrangement foraccommodating the drive mechanismfor actuating the contacts of thebreaker, the housing arrangement being at high-voltage potential whenthe breaker is in service and being arranged within the enclosure, thehousing arrangement comprising a housing member disposed in surroundingrelation to the drive mechanism,a plurality of reinforcement ribsprovided on at least the outer surface of saidhousing member, at leasttwo shell-like members made of electrically conductive material, said Ishell-like members conjointly forming a hollow cylinmember havingrespective end-face portions extending member having respective end-faceportions'extending radially in covering relation to said reinforcementribs, said fastening means comprising means for self-holding saidhalf-shells fixedly between said end-face portions.

4. The housing arrangement of claim 2, said housing radially in coveringrelation to said reinforcement ribs, 5. The housing arrangement of claim4, said fastening said fastening means comprising slot means formed ineach of said end-face portions at the periphery thereof, and inwardlydirected projection means formed on the longitudinal ends of each ofsaid half-shells for engag- Shells to Said endface Portionsingcorresponding ones of said slot means.

means comprising ancillary fastening means in the form ofa plurality ofthreaded members for joining said half-

1. In a high-voltage apparatus such as a compressed-gas circuit breakeror the like having an enclosure wherein an electric field is presentwhen the breaker is in service, a reinforced housing arrangement foraccommodating the drive mechanism for actuating the contacts of thebreaker, the housing arrangement being at high-voltage potential whenthe breaker is in service and being arranged within the enclosure, thehousing arrangement comprising a housing member disposed in surroundingrelation to the drive mechanism, a plurality of reinforcement ribsprovided on at least the outer surface of said housing member, at leasttwo shell-like members made of electrically conductive material, saidshell-like members conjointly forming a hollow cylinder and beingarranged in surrounding relation to said outer surface of said housingmember whereby impairment of the electric field within the enclosure isprecluded, and fastening means for self-holding and shell-like membersto said housing member.
 2. The housing arrangement of claim 1, saidshell-like members being two in number and being respective half-shells.3. The housing arrangement of claim 2, said housing member havingrespective end-face portions extending radially in covering relation tosaid reinforcement ribs, said fastening means comprising means forself-holding said half-shells fixedly between said end-face portions. 4.The housing arrangement of claim 2, said housing member havingrespective end-face portions extending radially in covering relation tosaid reinforcement ribs, said fastening means comprising slot meansformed in each of said end-face portions at the periphery thereof, andinwardly directed projection means formed on the longitudinal ends ofeach of said half-shells for engaging corresponding ones of said slotmeans.
 5. The housing arrangement of claim 4, said fastening meanscomprising ancillary fastening means in the form of a plurality ofthreaded members for joining said half-shells to said end-face portions.